<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>淘宝轮播图</title>
    <style>
        * {
            padding: 0;
            margin: 0;
        }

        /* 清除ul无序列表里的小圆点 */
        li {
            list-style: none;
        }

        .tb-prom {
            position: relative;
            width: 520px;
            height: 280px;
            background-color: pink;
            margin: 100px auto;
        }

        .tb-prom img {
            width: 520px;
            height: 280px;
        }

        .tb-prom .prew,
        .next {
            position: absolute;
            top: 50%;
            margin-top: -15px;
            width: 20px;
            height: 30px;
            background-color: rgba(0, 0, 0, .3);
            text-align: center;
            color: #ffffff;
            line-height: 30px;
            text-decoration: none;
        }

        /* 下面注释掉的内容都是两个类名里重复的、公共的，可以并集调用的，所以在上面添加一个并集选择器以节省代码 */
        .tb-prom .prew {
            /* position: absolute; */
            left: 0px;
            /* top: 50%;
             margin-top: -15px;
             width: 20px;
             height: 30px;
             background-color: rgba(0, 0, 0, .3);
             text-align: center;
             color: #ffffff;
             line-height: 30px;
             text-decoration: none; */
            border-top-right-radius: 15px;
            border-bottom-right-radius: 15px;
        }

        .tb-prom .next {
            /* position: absolute; */
            right: 0px;
            /* top: 50%;
             margin-top: -15px;
             width: 20px;
             height: 30px;
             background-color: rgba(0, 0, 0, .3);
             text-align: center;
             color: #ffffff;
             line-height: 30px;
             text-decoration: none; */
            border-top-left-radius: 15px;
            border-bottom-left-radius: 15px;
        }
        .tb-prom .promo-nav {
            position: absolute;
            left: 50%;
            margin-left: -35px;
            bottom: 10px;
            width: 70px;
            height: 15px;
             background-color:rgba(255, 255, 255, .3);
            border-radius:7px;
        }
        .tb-prom .promo-nav li {
            float: left;
            width: 8px;
            height: 8px;
            background-color: #ffffff;
            border-radius: 4px;
            margin: 3px;
        }
        .tb-prom .promo-nav .selected {
            background-color: #ff5000;
        }
        
    </style>
</head>

<body>
    <div class="tb-prom">
        <img src="images/tb.jpg" alt="">
        <a href="#" class="prew">&lt;</a>
        <a href="#" class="next">&gt;</a>
      <ul class="promo-nav">
          <li class="selected"></li>
          <li></li>
          <li></li>
          <li></li>
          <li></li>
      </ul>
    </div>
</body>

</html>